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Neumann KH420 Review (Studio Monitor)

Rate this speaker:

  • 1. Poor (headless panther)

    Votes: 2 0.5%
  • 2. Not terrible (postman panther)

    Votes: 2 0.5%
  • 3. Fine (happy panther)

    Votes: 26 6.2%
  • 4. Great (golfing panther)

    Votes: 392 92.9%

  • Total voters
    422

Ron Texas

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As far as I know the KH420 uses a switched power supply which (at a combined amp power of 600 W - almost twice of the ATC50SCM pro) also results in a significant loss of weight.
Whatever it weighs, it's too much for our host to lug upstairs. They have Impressive measured performance combined with the often missing dynamic range.
 

Ron Texas

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dfuller

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The ATC drive units are seriously overbuilt and it was a selling point in my day selling and owning the brand. My original 100A bass drivers even had a sodding great 'heatsink' kind of affair over the magnet (abandoned in the SL version of the driver I remember). The Neumann almost certainly uses more contemporary driver chassis' (I know nothing of their mid dome) which won't be as heavy.

By the way, the raw carcass of my 100A's was actually rather light considering it's size and built-up bulk. I believe it was damped MDF from memory and models like mine had wool filling held by stapled netting. No idea what Neumann do to the innards of their cabs but I'm sure it's well researched...
It's a neodymium motor, so much smaller than the ATC's ferrite motor. ATC's motors in general are absurdly huge, probably to improve sensitivity given the driver's high mms (at least with the woofers, the midrange is "because they can" lol).
 

dc655321

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I wonder if this has to do with Genelec's group delay characteristics, because I've noticed this with other Genelecs as well. The KH420 has super low GD for a ported design (going by Neumann's data, which we know to be accurate) - under 1 cycle all the way down to 20hz.
KH420_Group_Delay_510.gif


Compare that to the 8361... Still excellent, but considerably higher.
8361A_Extended_Phase_Linearity_OFF_GD.png

Um, those plots really similar until the 8361 cuts off at 50Hz.
As in, what are you basing your speculation on?
 

FeddyLost

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On the topic of the KH420, it competes handily with the ATC SCM50ASL Pro, which is close to twice the price.
I think that KH420 will be significantly better in department of LF extension and proper comparison would need at least a good set of measurements of SCM50ASL.
But maybe ATC is really will be better for studio duties for some people. This price level always needs personal evaluation.
 

Pearljam5000

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ATC's dome mid is considered to be the best in the world ( from what i read)
How does the KH420s dome mid compares to it?
 

Frank Dernie

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ATC's dome mid is considered to be the best in the world ( from what i read)
How does the KH420s dome mid compares to it?
The two big differences are the ATC has a wider frequency range at the low end allowing the crossover frequency to be lower (380Hz in ATC SCM50 v 570Hz in KH420) FWIW and the one in the kH420 has reportedly more benign breakup modes giving lower distortion.
 

thewas

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The two big differences are the ATC has a wider frequency range at the low end allowing the crossover frequency to be lower (380Hz in ATC SCM50 v 570Hz in KH420) FWIW and the one in the kH420 has reportedly more benign breakup modes giving lower distortion.
Here are the distortion differences
 

DjBonoBobo

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In the printed version of the KH310 review, soundandrecording included this comparison of the Neumann dome with "a dome midrange of the same size from a different manufacturer"

Left Neumann, right Other @2khz

1651737169582.png


I don´t know if there is or was a third midrange dome of that size other than the ATC?

Edit: They write "In comparison, a calotte of the same size from another manufacturer."
I am assuming it was a dome from the picture, but they did not actually write that.
 

xema

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Kh750 a micro subwoofer. Are you aware what you wrote?
subbass from a 10inch sub speaker is better than subbass from a normal 10inch bass speaker

and this is what KH says:

KH 420 G​

Powerful tri-amplified midfield studio monitor – high-precision dispersion with tremendous sound level reserves.​

  • Computer-modeled cabinet design using Low Resonance Integral Molding (LRIM™) materials
  • Extraordinary bass depth (26 Hz) with high sound pressure (122.4 dB)
  • Precise dispersion in the midrange and high frequencies
  • As a stereo system with KH 750 DSP and optional tools, controllable and alignable to the room
 

DSJR

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In the printed version of the KH310 review, soundandrecording included this comparison of the Neumann dome with "a dome midrange of the same size from a different manufacturer"

Left Neumann, right Other @2khz

View attachment 204606

I don´t know if there is or was a third midrange dome of that size other than the ATC?

Edit: They write "In comparison, a calotte of the same size from another manufacturer."
I am assuming it was a dome from the picture, but they did not actually write that.
The similar dome PMC use(d) was made for them by Audax eventually I gather. No idea if that's still the case. ATC also changed the flare of the heavy waveguide some time back and this may also make a good measured difference as well as a visual change.
 

Frgirard

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subbass from a 10inch sub speaker is better than subbass from a normal 10inch bass speaker

and this is what KH says:

KH 420 G​

Powerful tri-amplified midfield studio monitor – high-precision dispersion with tremendous sound level reserves.​

  • Computer-modeled cabinet design using Low Resonance Integral Molding (LRIM™) materials
  • Extraordinary bass depth (26 Hz) with high sound pressure (122.4 dB)
  • Precise dispersion in the midrange and high frequencies
  • As a stereo system with KH 750 DSP and optional tools, controllable and alignable to the room
The marketing is king. You throw in the trash all the
Job made by ASR to open the eyes of the audiophile.
 

Frank Dernie

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In the printed version of the KH310 review, soundandrecording included this comparison of the Neumann dome with "a dome midrange of the same size from a different manufacturer"

Left Neumann, right Other @2khz

View attachment 204606

I don´t know if there is or was a third midrange dome of that size other than the ATC?

Edit: They write "In comparison, a calotte of the same size from another manufacturer."
I am assuming it was a dome from the picture, but they did not actually write that.
I don't dispute the new dome behaves better but showing the mode shape at a single frequency tells little and choosing a different frequency may well give the opposite impression.
 

DjBonoBobo

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I don't dispute the new dome behaves better but showing the mode shape at a single frequency tells little and choosing a different frequency may well give the opposite impression.

I'm not technically familiar with it, but as I understand the review, the idea was that the midrange driver doesn't need to manage more than 2khz and apparently the problem becomes more difficult at higher frequency. I therefore understand it as a "worst case" picture. But i don´t know if I understood it correctly.
It is perhaps also not so important, because there are also other measurements to the distortions.
 

Frank Dernie

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I'm not technically familiar with it, but as I understand the review, the idea was that the midrange driver doesn't need to manage more than 2khz and apparently the problem becomes more difficult at higher frequency. I therefore understand it as a "worst case" picture. But i don´t know if I understood it correctly.
It is perhaps also not so important, because there are also other measurements to the distortions.
Indeed, the extent to the problems introduced by non-pistonic motion of the driver diaphragm depends on the frequency bandwidth being used, the crossover slopes and the damping, but the likelihood of both domes having the same modes at the same frequency is near zero, so a snapshot at one frequency where one dome is at one of its resonant modes whilst the other is not is not that informative.

Having written that in the snapshot you posted the Neumann dome is near its first breakup mode indicating it is behaving like a piston below whereas the ATC looks like it is at a second or third more complex mode indicating that it has been radiating modally from a lower frequency.

I have always felt having all drivers only working in the frequency range where they remain pistonic is the ideal but most drivers aren't stiff enough for this and radiate modally over part of their range, in fact it is the exploitation of this characteristic that gave rise to NXT and BMR drivers.
 

FeddyLost

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I don´t know if there is or was a third midrange dome of that size other than the ATC?
D7608-920010 for example. Cheap one.

subbass from a 10inch sub speaker is better than subbass from a normal 10inch bass speaker
I'd say that KH750 is not a JL Audio at all and it will be more beneficial from DSP and lower GD than from some special subbass capability.
If we accept that we are extremely insensitive to LF distortion, then it might be OK, but it looks like KH420 would require a pair of 750s per channel ...
 

DjBonoBobo

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I'd say that KH750 is not a JL Audio at all and it will be more beneficial from DSP and lower GD than from some special subbass capability.
If we accept that we are extremely insensitive to LF distortion, then it might be OK, but it looks like KH420 would require a pair of 750s per channel ...

I wonder if Neumann has plans to develop an 810 and 870 with DSP. The software had to support multichannel first, though, if they want to keep the multichannel-abilities of the 810 and 870. The 810 has roughly 2x the power of a 750, more fitting for the 420. The 810 is huge, though, and its form factor not very practical for home use, IMHO.
 
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